I've split the versions of TBird into a thunderbird-esr release, now up to 24.7.0, and a standard thunderbird, now up to 31.0. They can't be installed at the same time, since I also added symlinks in /usr/bin for the programs. If you want to stay with the ESR version, just switch to thunderbird-esr. The symlinks "thunderbird" and "thunderbird-esr" will both start version 24.7.0. Thunderbird 31.0 just has "thunderbird". The new versions should appear in the testing CR shortly.

As usual, please let us know how they install and work. Thunderbird 31.0 will reject the older versions of the lightning extension, but have it search for a newer version and it should find and install Lightning 3.3.

The latest Thunderbird 31.4.0 + the language packs are now in the test CR
Edit: this include the esr version and is good for MX/M12, M11 & m8.5/

What's new you ask?

"The previous issues with jp mac builds have now been fixed, and Thunderbird will no longer need to be run in 32-bit mode, and installing extensions within Thunderbird no longer requires download and installing as a file," reads the official changelog.

The devs also explained that various memory safety issues have been fixed, the sendBeacon requests now have the Origin header, and a problem with cookie injection has been corrected.

Per m_pav's recommendation, we decided to put the new releases straight into the main CR, after the packager tests for installation and usability. After all, this is what you'd get if you did the straight upgrade from Mozilla from the nag screen.